Robotic inventory systems

Abstract

Embodiments of a robotic inventory system are provided that include a mobile robot for inventorying an inventory area, such as store or warehouse. The mobile robot can move through the inventory area collecting data from tagged items (e.g., RFID tags). Based on the collected data, the robotic inventory system can determine the items in the inventory area and the location of those items. In some embodiments, no additional infrastructure is needed for the installation of the robotic inventory system. This can allow, for example, the inventorying system to be shipped to an end customer and used by the end customer without having a professional installer setup the robot and/or the inventorying system.

The following is claimed: 
     
         1 . A mobile robotic device for inventorying items, the mobile robotic device comprising:
 a navigation module configured to identify the boundaries of an inventory storage area and automatically determine a search route through the inventory storage area;   a propulsion module configured to receive the search route from the navigation module and move the mobile robotic device along the search route;   an RFID reader configured to receive multiple RFID readings from RFID tags associated with inventory items, the multiple RFID readings received along multiple locations along the search route; and   an inventory locator module, the locator module configured to identify the location of inventory items within the inventory storage area based at least partly on the multiple RFID readings from the multiple locations.   
     
     
         2 . The robotic device of  claim 1 , further comprising a location tracking module configured to determine location data for the mobile robotic device. 
     
     
         3 . The robotic device of  claim 2 , wherein the inventory locator module is configured to determine the location of the inventory items based at least partly on the location data for the mobile robotic device. 
     
     
         4 . The robotic device of  claim 2 , wherein the location tracking module includes a dead reckoning system for determining the current location. 
     
     
         5 . The robotic device of  claim 1 , wherein the search route is updated based at least partly on detected obstacles. 
     
     
         6 . The robotic device of  claim 5 , wherein the detected obstacles include inventory items identified by their associated RFID tags. 
     
     
         7 . The robotic device of  claim 1 , wherein the search route is calculated based at least partly on a previous inventory scan of the inventory storage area. 
     
     
         8 . A robotic inventory system for inventorying items, the system comprising:
 a mobile robot having an electronic tag reader configured to receive electronic tag data from electronic tags associated with inventory items;   a navigation module configured to determine a search route through an inventory area and direct the mobile robot to move along the search route; and   an inventory identification module configured to receive the electronic tag data from the mobile robot and identify the inventory items in the inventory area based at least partly on the electronic tag data;   wherein the mobile robot is configured to collect multiple readings from one or more of the electronic tags associated with the inventory items, the multiple readings taken at multiple locations along the search route.   
     
     
         9 . The robotic system of  claim 8 , further comprising an inventory location module configured to identify the location of the inventory items within the inventory storage area based at least partly on the multiple readings from the multiple locations. 
     
     
         10 . The robotic system of  claim 9 , wherein the inventory location module is configured to identify the location of the inventory items by triangulating the location of the inventory items from the multiple readings from the multiple locations. 
     
     
         11 . The robotic system of  claim 8 , wherein the mobile robot collects signal characteristics of the multiple readings, including signal strength. 
     
     
         12 . The robotic system of  claim 11 , further comprising an inventory location module configured to identify the location of the inventory items within the inventory storage area based at least partly on the multiple RFID readings and the signal characteristics of the multiple readings. 
     
     
         13 . The robotic system of  claim 8 , wherein the electronic tags are RFID tags. 
     
     
         14 . The robotic system of  claim 8 , wherein electronic tag reader includes directional antennas. 
     
     
         15 . The robotic system of  claim 8 , wherein the electronic tag data is used to identify obstacles in the search route and the navigation module is configured to update the search route based on the identified obstacles. 
     
     
         16 . A method for inventorying a storage area using a mobile robot, the method comprising:
 moving the mobile robot to a first area;   collecting inventory data related to the one or more RFID tags associated with inventory items using an RFID reader from the first area;   moving the mobile robot to a second area;   collecting inventory data related to the one or more RFID tags using the RFID reader from the second area; and   determining location of the inventory items based at least partly on the inventory data collected from the first area and the second area.   
     
     
         17 . The method of  claim 16 , wherein the inventory data includes the location of the first area and the second area. 
     
     
         18 . The method of  claim 17 , wherein determining the location of the inventory items comprises:
 determining a first range to the one or more RFID tags from the mobile robot at the first area;   determining a second range to the one or more RFID tags from the mobile robot at the second area; and   determining the location of the inventory items in the storage area based at least on the first range, the second range, and the locations of the first area and the second area.   
     
     
         19 . The method of  claim 18 , wherein the first range is calculated based on return phase angles at different frequencies of signals sent from the RFID reader. 
     
     
         20 . The method of  claim 16 , wherein the inventory data includes signal strengths of the signals received from the one or more RFID tags. 
     
     
         21 . The method of  claim 20 , wherein determining the location of the inventory items is based at least partly on the signal strengths of the signals from the one or more RFID tags. 
     
     
         22 . The method of  claim 16 , wherein determining the location of the inventory items is performed on the mobile robot. 
     
     
         23 . The method of  claim 16 , wherein determining the location of the inventory items is performed on an inventory management system separate from the mobile robot after the mobile robot communicates the inventory data to the inventory management system.